Expanded Folders - not an option

The help file says " You can enable or disable expandable folders from the [File Displays / Folder Expansion] Preferences page." That's not in my preferences!

Is that DO12 preferences?

Folder expansion is a D13 option:

I do have 12.33. But my "check for updates" says I'm current! And I don't even see anything about v13 on the website??? Is it a download for v12 users or an upgrade fee. And where's info about it?

You are current for DO12. DO13 is in beta: